1. Field of the Invention
The present invention relates to a moving robot with an arm mechanism, and in particular, to a moving robot with an arm mechanism that loads and transports an article on the robot, which moves within a house or within a building such as a facility, the moving robot being used for services.
2. Description of the Related Art
In recent years, various service robots sharing activity spaces with people have come onto the market. Arms are mounted on a main robot body to access a specified article, handle the target article, and carry the gripped article in accordance with instructions from a human operator. A large number of robots on which arms are thus mounted have been proposed. Such robots are disclosed in, for example, Jpn. Pat. Appln. KOKAI Publication No. 2004-230509 “Moving Robot” and Naoto KAWAUCHI and four others, “Home Use Robots ‘wakamura’”, Mitsubishi Heavy Industries, LTD. Technical Report, Mitsubishi Heavy Industries, LTD., September 2003, Vol. 40, No. 5, P. 270 to 273. The service robots disclosed in these documents normally have mounted arms attached to the laterally opposite sides of the main body. Consequently, while the service robot is moving, for example, to transport an article, the mounted arms may collide against surrounding objects or damage a person or make him or her fear the robot when it crosses the person. These robots are thus considered to be insufficiently safe. Accordingly, in the conventional service robots, the arms mounted on a moving carrier are covered with an opening and closing cover provided separately from the arms, in order to improve safety and to prevent users from fearing the robots.
If the arm housing opening and closing cover is provided as described in Jpn. Pat. Appln. KOKAI Publication No. 2004-230509, it is placed so as to cover the whole arms. This disadvantageously increases the size of the moving robot itself. Further, the moving robot requires the cover to be opened and closed every time the arms are extended. Thus, disadvantageously, the arm extending operation requires a long time and is cumbersome. Some service robots are configured so that the arms can be folded for housing. These service robots can be made compact by folding the arms. However, the size of the mounted robot itself, including the length of its arms, needs to be increased in order to widen the range within which the arms are movable in picking up or placing an article. This is not preferable in terms of safety.